Biomechanical testing of hip protectors following the Canadian Standards Association express document

Abstract

A variety of hip protectors are available, but it is not clear which is the most effective and there is no standard test to evaluate their performance. This is the first study that uses a standard mechanical test on hip protectors. Some protectors perform well but others are almost ineffective, providing little to no protection to the wearer during a fall. Introduction: Each year, over 70,000 patients are admitted to hospital in the UK with hip fractures. There are a variety of commercial hip protectors currently available. However, it is not explicitly clear which is the most effective with regard to maximum force attenuation, whilst still being both comfortable for the user and providing reasonable force reduction if misplaced from the intended position. The numerous test methods reported in the literature have given conflicting results, making objective comparison difficult for users, researchers, and manufacturers alike. The Canadian Standards Association (CSA) has therefore published an express document (EXP-08-17) with a draft standard test method. This paper presents initial results for a range of hip protectors. Methods: Eighteen commercially available hip protectors were tested according to EXP-08-17. Each hip protector was impacted five times in correct anatomical alignment over the greater trochanter and once at 50 mm displacements in the anterior, posterior, and lateral directions. Results: Considerable differences were identified between individual hip protectors in their ability to reduce impact forces on the femur (between 3% and 36% reduction in peak force). The performance was reduced when misplaced in many cases (maximum reduction only 20%). Conclusions: This is the first study that uses a standard mechanical test on hip protectors. Previous studies have used a variety of methods, making it difficult to interpret results. We hope that these results using a standard test method will facilitate the effective comparison of results, as well as providing useful data for clinicians, users, and purchasers.

A comparison of floor surfaces for injury prevention in care settings: impact forces and horizontal pulling force required to move wheeled equipment

“…This study has used the same test method for assessing hip protectors (as described in the CSA Standard) to assess the impact properties of a number of commercially available floor samples. These biomechanical testing methods have been previously used to assess the peak force reduction during a simulated fall of eighteen commercially available hip protectors [36]. It is interesting to note that the force attenuation for these hip protectors ranged from 3 -36 %, and in this study the force attenuated by the floor surfaces was 0.7 -25 %.…”

“…The test set-up for the mechanical impact of the flooring has previously been described in an existing study by Keenan et al [36]. A simplified version of the method is given below, but further details can be found in the previous study.…”

“…The silicone soft tissue simulant covering the aluminium femur form was made using Jacobson Chemicals RTV (room-temperature-vulcanizing) C204 silicone rubber, 81b catalyst and 10% silicone oil. The silicone was cured in a custom-made mould [36]. The condensation cure silicone was then placed in the oven at 40 °C and left for three days to fully cure.…”

A Description of Novel Uses of Hip Protectors in an Elderly Hip Fracture Population: A Technical Report

“…They can be broadly classified into hip protectors where padding with soft, energy-absorbing material is used and hip protectors where semi-rigid material is used that diverts the force away from the trochanteric region to the soft tissues of the thigh [ 7 ]. Keenan and Evans performed biomechanical testing using a standardised test to compare individual hip protectors in their effectiveness in preventing hip fractures [ 8 ]. They found that there were significant differences in the effectiveness of individual hip protectors in their ability to reduce the impact forces [ 8 ].…”

“…Keenan and Evans performed biomechanical testing using a standardised test to compare individual hip protectors in their effectiveness in preventing hip fractures [ 8 ]. They found that there were significant differences in the effectiveness of individual hip protectors in their ability to reduce the impact forces [ 8 ].…”